﻿using System;
using System.Runtime.InteropServices;

namespace CozyDump.Api
{
    public static class Kernel32Api
    {
        [DllImport("kernel32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        public static extern bool CloseHandle(IntPtr hObject);
        public static IntPtr INVALID_HANDLE_VALUE = new IntPtr(-1);

        [Flags]
        public enum EFileAccess : uint
        {
            //
            // Standart Section
            //

            AccessSystemSecurity = 0x1000000,   // AccessSystemAcl access type
            MaximumAllowed = 0x2000000,     // MaximumAllowed access type

            Delete = 0x10000,
            ReadControl = 0x20000,
            WriteDAC = 0x40000,
            WriteOwner = 0x80000,
            Synchronize = 0x100000,

            StandardRightsRequired = 0xF0000,
            StandardRightsRead = ReadControl,
            StandardRightsWrite = ReadControl,
            StandardRightsExecute = ReadControl,
            StandardRightsAll = 0x1F0000,
            SpecificRightsAll = 0xFFFF,

            FILE_READ_DATA = 0x0001,        // file & pipe
            FILE_LIST_DIRECTORY = 0x0001,       // directory
            FILE_WRITE_DATA = 0x0002,       // file & pipe
            FILE_ADD_FILE = 0x0002,         // directory
            FILE_APPEND_DATA = 0x0004,      // file
            FILE_ADD_SUBDIRECTORY = 0x0004,     // directory
            FILE_CREATE_PIPE_INSTANCE = 0x0004, // named pipe
            FILE_READ_EA = 0x0008,          // file & directory
            FILE_WRITE_EA = 0x0010,         // file & directory
            FILE_EXECUTE = 0x0020,          // file
            FILE_TRAVERSE = 0x0020,         // directory
            FILE_DELETE_CHILD = 0x0040,     // directory
            FILE_READ_ATTRIBUTES = 0x0080,      // all
            FILE_WRITE_ATTRIBUTES = 0x0100,     // all

            //
            // Generic Section
            //

            GenericRead = 0x80000000,
            GenericWrite = 0x40000000,
            GenericExecute = 0x20000000,
            GenericAll = 0x10000000,

            SPECIFIC_RIGHTS_ALL = 0x00FFFF,
            FILE_ALL_ACCESS =
            StandardRightsRequired |
            Synchronize |
            0x1FF,

            FILE_GENERIC_READ =
            StandardRightsRead |
            FILE_READ_DATA |
            FILE_READ_ATTRIBUTES |
            FILE_READ_EA |
            Synchronize,

            FILE_GENERIC_WRITE =
            StandardRightsWrite |
            FILE_WRITE_DATA |
            FILE_WRITE_ATTRIBUTES |
            FILE_WRITE_EA |
            FILE_APPEND_DATA |
            Synchronize,

            FILE_GENERIC_EXECUTE =
            StandardRightsExecute |
              FILE_READ_ATTRIBUTES |
              FILE_EXECUTE |
              Synchronize
        }

        [Flags]
        public enum EFileShare : uint
        {
            /// <summary>
            /// 
            /// </summary>
            None = 0x00000000,
            /// <summary>
            /// Enables subsequent open operations on an object to request read access. 
            /// Otherwise, other processes cannot open the object if they request read access. 
            /// If this flag is not specified, but the object has been opened for read access, the function fails.
            /// </summary>
            Read = 0x00000001,
            /// <summary>
            /// Enables subsequent open operations on an object to request write access. 
            /// Otherwise, other processes cannot open the object if they request write access. 
            /// If this flag is not specified, but the object has been opened for write access, the function fails.
            /// </summary>
            Write = 0x00000002,
            /// <summary>
            /// Enables subsequent open operations on an object to request delete access. 
            /// Otherwise, other processes cannot open the object if they request delete access.
            /// If this flag is not specified, but the object has been opened for delete access, the function fails.
            /// </summary>
            Delete = 0x00000004
        }

        public enum ECreationDisposition : uint
        {
            /// <summary>
            /// Creates a new file. The function fails if a specified file exists.
            /// </summary>
            New = 1,
            /// <summary>
            /// Creates a new file, always. 
            /// If a file exists, the function overwrites the file, clears the existing attributes, combines the specified file attributes, 
            /// and flags with FILE_ATTRIBUTE_ARCHIVE, but does not set the security descriptor that the SECURITY_ATTRIBUTES structure specifies.
            /// </summary>
            CreateAlways = 2,
            /// <summary>
            /// Opens a file. The function fails if the file does not exist. 
            /// </summary>
            OpenExisting = 3,
            /// <summary>
            /// Opens a file, always. 
            /// If a file does not exist, the function creates a file as if dwCreationDisposition is CREATE_NEW.
            /// </summary>
            OpenAlways = 4,
            /// <summary>
            /// Opens a file and truncates it so that its size is 0 (zero) bytes. The function fails if the file does not exist.
            /// The calling process must open the file with the GENERIC_WRITE access right. 
            /// </summary>
            TruncateExisting = 5
        }

        [Flags]
        public enum EFileAttributes : uint
        {
            Readonly = 0x00000001,
            Hidden = 0x00000002,
            System = 0x00000004,
            Directory = 0x00000010,
            Archive = 0x00000020,
            Device = 0x00000040,
            Normal = 0x00000080,
            Temporary = 0x00000100,
            SparseFile = 0x00000200,
            ReparsePoint = 0x00000400,
            Compressed = 0x00000800,
            Offline = 0x00001000,
            NotContentIndexed = 0x00002000,
            Encrypted = 0x00004000,
            Write_Through = 0x80000000,
            Overlapped = 0x40000000,
            NoBuffering = 0x20000000,
            RandomAccess = 0x10000000,
            SequentialScan = 0x08000000,
            DeleteOnClose = 0x04000000,
            BackupSemantics = 0x02000000,
            PosixSemantics = 0x01000000,
            OpenReparsePoint = 0x00200000,
            OpenNoRecall = 0x00100000,
            FirstPipeInstance = 0x00080000
        }

        [DllImport("kernel32.dll",
          SetLastError = true,
          CharSet = CharSet.Auto)]
        public static extern IntPtr CreateFile(
                string lpFileName,
                EFileAccess dwDesiredAccess,
                EFileShare dwShareMode,
                IntPtr lpSecurityAttributes,
                ECreationDisposition dwCreationDisposition,
                EFileAttributes dwFlagsAndAttributes,
                IntPtr hTemplateFile
            );

        [DllImport("Kernel32", CharSet = CharSet.Auto, SetLastError = true)]
        public static extern IntPtr CreateFileMapping(
                                         IntPtr hFile,
                                         UInt32 lpAttributes,
                                         AllocationProtect flProtect,
                                         UInt32 dwMaxSizeHi,
                                         UInt32 dwMaxSizeLow,
                                         string lpName
                                         );

        [DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
        public static extern IntPtr MapViewOfFile(
                                               IntPtr hFileMappingObject,
                                               UInt32 dwDesiredAccess,
                                               UInt32 dwFileOffsetHigh,
                                               UInt32 dwFileOffsetLow,
                                               UInt32 dwNumberOfBytesToMap
            );

        [DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
        public static extern IntPtr MapViewOfFileEx(IntPtr hFileMappingObject,
                                               UInt32 dwDesiredAccess,
                                               UInt32 dwFileOffsetHigh,
                                               UInt32 dwFileOffsetLow,
                                               UInt32 dwNumberOfBytesToMap,
                                               IntPtr PreferredAddress
                                               );

        [DllImport("kernel32.dll", SetLastError = false, CharSet = CharSet.Auto)]
        public static extern bool UnmapViewOfFile(
              IntPtr lpBaseAddress
            );

        public const int FILE_MAP_READ = 4;
        public const int FILE_MAP_WRITE = 2;

        [Flags()]
        public enum AllocationProtect
        {
            PAGE_EXECUTE = 0x10,
            PAGE_EXECUTE_READ = 0x20,
            PAGE_EXECUTE_READWRITE = 0x40,
            PAGE_EXECUTE_WRITECOPY = 0x80,
            PAGE_NOACCESS = 0x1,
            PAGE_READONLY = 0x2,
            PAGE_READWRITE = 0x4,
            PAGE_WRITECOPY = 0x8,
            PAGE_GUARD = 0x100,
            PAGE_NOCACHE = 0x200,
            PAGE_WRITECOMBINE = 0x400
        }
    }
}
